Furnace.



J. B. LADD & D. BAKER. FURNACE.

ABPLIOATION FILED .DEO 17 -1908 Patented Aug. 23, 1910.

WITNESSES: Y

ATTOR/VE 2 UNITED STATES ATENT OFFICE.

JANIES B. LAIDD AND DAVID BAKER, OF PHILADELPHIA PENNSYLVANIA, ASSIGNORST0 LADD & BAKER, INCORPORATED, A CQBPORATION OF PENNSYLVANIA.

FURNACE.

Applicgtion fileafiaeeember 17, 1908. Serial No. 467,951.

To all whom it may concern:

Be it known that we, JAMES B. LADD and have i vented a new and usefulImprovement in Furnaces, of which t he,following is a specification.

This invention has reference to the treatment of ores, and ref morepafticularly to a furnace or kiln for treating or roasting iron pyrites,for the purpose of effectually freeing the iron of sulfur, anddelivering the latter in the form of a rich sulfurousacid gas.

The invention consists of a kiln or fur nace embodying a roastingchamber in which the ore is treated, and an improved arran ement oftemperature controlling flues, y means of which the degree of heat towhich the ore is subjected in the roasting chamber may be nicely andaccurately controlled, according to the nature of the ore being treatedas regards the quantity of sulfur therein, and the changing conditionswhich take place as the roasting operation progresses.

Referrin to the drawings: Figure 1 is a side elevation of our improvedfurnace. Fig. 2 is a longitudinal section through the same on the lineaa of Fig. 3. 'Fig.

3 is an end elevation of the receiving end of the furnace, that intowhich the raw ore is delivered. Fig. 4 is a similar view of thedischarge end of the furnace, that where the residue is discharged. Fig.5 is a transverse section on the .line 6- of Fig. 2. Fig. 6 is alongitudinal section through the nozzle and its controlling valve on anenlarged scale, showingthe valve set so as to permit the heated air fromthe annular chamber 35 to enter the nozzle and be discharged into theheating chamben. Fig. is a similar view showing the valve setso as todeflect the heated air'from the annular chamber and discharge it to .theoutside.

In the accompanylng drawings: 1 repre-Q sents a shell or cylinderconstituting the.

furnace or kiln proper, which is sustained as usual at a slightinclination downward from its receiving end, and rotably sup ported by'means' of rollers 2, or by other suitable means, so that may haveimparted to it a slow rotary motion, convene iently by means of a drivepinion 3 engag1 DAVID BAKER, of Philadelphia, county of" Philadelphia,and State of Pennsylvania,

ing a rack 4 on the exterior of the cylinder, this motion of thecylinder causing the ore, which is delivered into'the up er receivingend, to travel slowly and um ormly to the lower delivery end, beingsubjected in. its passage through the cylinder to a tumbling oragitating action. T

At its receiving end the interior of the cylinder communicates with achamber 5 inclosed by a fixed cylindrical casing 6, formed with anupwardly extending neck 7 Patented Aug. 23, 1910.

into which the raw ore is fed from a feed hopper 8 at the side of theneck, an inclined chute 9 being fixed within the chamber 5 and extendinginto the roasting chamber, to receive the ore from the neck and deliverthe same tothe roasting chamber. The said neck serves also as a meansfor the escape of the sulfur-gases, which pass upwardly into a pipe 10connecting with the neck, from which they may be collected for use. Atits delivery end the cylinder communicates with a chamber 11,- inclosedby a fixed casing 12, -for receiving the residue-or roasted ore, whichlatter is discharged from the receiving chamber by means of a belldischarge valve ].3.

The cylinderl is formed of fire-brick in Y which are arranged side byside, as shown in Fig. 5, a series of longitudinal temperaturecontrolling flues 14, 15, 16, 17 etc., certain of said flues, everyalternate one as indicated by the odd numbers, beingfor the circulationof either air or heating gases; while the other flues are for thepassage of air only, the primary purpose of this construction andarrangement being, as will be 'more fully described hereinafter, for theproper regulation of the temperature in the roasting chamber to-meet thevarying conditions encountered in the operation of the furnace asregards the character of the ore being treated, etc. At its ends, thebrick- :work or shell of the cylinder is thickened or 'eniarged, theflues 14, 16, 18, etc., being defiected outwardly at the receiving endof the'cylinder, and passing through the thickened portion of the same,as at 72, whereby they will terminate in a circular line outside of andbeyond the ends of the alternate fiues 15, 1?, 19, etc., which latterpass straight through the thickened portion of the shell at this point.At the opposite or delivery end of the furnace, this arrangement of thefines is reversed, the flues 15, 17, 19, etc, being deflected, as at 0,and terminating in a circular, line beyond the ends of thealternatefiues 14:, 16, 18, etc., which latter pass straight through thethickened portion of the cylinder at this point, the purpose of whichconstruction and relative arrangement of the fines is to enable theproper circulation of heating gases and air, as will be presentlydescribed.

25 represents a starting or auxiliary furand will escape from theopposite ends of the fines into an annular chamber 28, surrounding thecylindrical casing 6 at the receiving end of the furnace, which latterchamber is inclosed by a fixed casing, and contains openings in its rearwall, with which the ends of the lines 15, 17, etc, are adapted toregister as the cylinder is rotated. The gases from this chamber 28 passdownwardly through an escape pipe 29 connected with'the chamber, fromwhich pipe the gases pass to a stack (not shown). The purpose of thisauxiliary or starting furnace is to heat the roastin chambersufficiently to cause the ignition o the pyrites when the raw ore is fedin, and inasmuch as with the ordinary commercial pyrites the temperatureof combustion, after being once started, is readily maintained andwithout auxiliary heat, and as it frequently becomes too high, thusfusing the mass of burning material and. seriously retarding combustion,1 propose to provide for the introduction into the fines 15, 17, etc.,of cold air instead of the gases, the efi ect oi which will be to reducethe temperature and prevent a too intense combustion. The air may-beintroduced by any appropriate means, for instance, by the naturalsuction of the stack, a suitable ad mission opening 30 being formed inthe annular chamber 27 to receive the air from the scenes chamber. Thisis efiected by means of a fan in its rear wall adapted to register withthe deflected ends of the fines 14L, 16, 18, etc, into which fines theair will pass as the cylinder 1 rotates, and passing through the fines,will become heated by the heat of combustion in the roasting chamber,and will escape from the opposite ends of the fines into a chamber 35inclosed by a fixed casing at the delivery end of the furnace, thischamber being formed in its front wall with openings adapted to registerwith the ends 01 the, fines. From the chamber 35 the heated air enters anozzle 36 extending through and sustained by the casing of the chamber,and projecting downwardly and inwardly with its delivery end terminatingwithin the delivery end of the roasting chamber, by which means theheated air, in the form of a blast, will be discharged into the roastingchamber, onto the ore therein. The cold air entering the fines 14, 16,18, etc., at the receiving end of the roasting chamber, has the effectof reducing the temperature at that point, where, under certainconditions itis likely to be too high, and by becoming heated by thishigh temperature, and being introduced into the delivery end of theroasting chamber, raises the temperature at this point, where, undercertain conditions, it is likely to be too low.

it is seen, therefore, that there are enibodied in the constructiondescribed, two means for. controlling the temperature in the roastinchamber, one the auxiliary fun nace and l ues in the shell connectedwith said furnace, which may be employed to heat up the roasting chamberor reduce the temperature therein at will, as by the banlring of thefire in the auxiliary furnace and the admission of cold air into saidlines; and the other by means of the fan or blower connected with thealternate flues in the shell of the cylinder, he cold air passingthrough said fiues, acting to take the heat from the part of the furnacewhere it may be too great, and delivering the same to that part whichmay require a high. temperature.

Under certain conditions it may not be necessary or desirable tointroduce the heated air flowing through fines 1 1, 16, 18, etc, intothe roasting chamber, although it may be desirable to effect such adegree of equalization of the temperatures at the two ends of theroasting chamber as would result merely from the passage of this airthrough the lines. Under these circumstances, the communication betweenthe annular chamher 35 and the nozzle may be controlled by a valve 37 ofsuch form, that the heated air will be prevented from entering theroastin'g chamber through the nozzle, and will be allowed to escape tothe outside through the outer end of the nozzle. Theconstrucr tion ofthe parts whereby this result may be effected, is shown articularly inFigs. 6 and 7, where it will lie seen that the annular chamber 35communicates with the nozzle 36 by means of a number iof openingsextending through the wall of the chamber, which openings are adapted tore "ster with corresponding openings in a ho low valve 37 mounted in t eouter end of the nozzle so as to rotate therein, -in order that theopenings in this valve may be brought into register with the openings inthe nozzle, or may be adjusted out of register, as shown in Fig. 6. Theinner endof the hollow valve is conical in form, so that when theopenings therein are out of register, the heated air may pass from thechamber 35 into the nozzle 36. When, however, the hollow valve 37 isturned to the position shown in Fig. 7 to bring the openings thereininto register with those throu h the walls of chamber 35, tge'heailteii1 air d t rou t e re 'sterin openings an escape outwfrdly thriugh' the open end of the valve. i

In the construction shown, particularlyin Fig. 2, the rear walls of thetwo annular chambers 33 and 28 are disposed in a single plane transverseto the axis of rotation of the cylinder which latter has its receivingend disposed in a similar plane and bearing flatly and closely a ainstthe said walls, the abutting surfaces eing of cast iron, machine-ground,and being maintained in close abutting relations, as the cylinderrotates. This construction, in connection with the fact that thesesurfaces 'are extended and of considerable area by reason of theprovision of two concentric annular chambers, and

the thickened end of the cylinder, reduces to a minimum the liability ofleakage of air into the c linder from the outside, so that there will eno danger of the dilution of the outfiowing freed gases by air. It willbeunderstood of course that the detailedeonstruction of our improvedfursa e-may be variously changed and modified bythei skilled mechanicwlthout departin the limits of my invention, provide its functions andoperations are substantially as above set forth, and it'is to 'beunderstood'that the invention is not limited to any specific form orarrangement of the parts, except in so' far as the limitations are sfxacified in the claims.

Having thus described our invention, what :we claim and desire to secureby Letters- Patent of the United States is as follows:

.1. In combination with a furnace having a heating chamber provided withtwo series of longitudinal flues surrounding the chamber, means for theindependent circulation om chamber 35 will flow and discharge ofdifferent temperature controlling me' two series of flues.

2. In combination with a furnace having a heating chamber provided withtwo series of longitudinal flues surrounding the chamber, means. forcirculating a temperature controlling medium through one series of fluesin-one direction, and means for circulating a different temperaturecontrolling medium through the other series .of flues in anoppositedirection, and independently of the first controlling medium, thedischa'r e of said controlling mediums being indepen ent of each other.

3. In combination with a furnace having 'a heating chamber provided withtwo series of longitudinal flues surrounding the chainher, theindividual flues of one series alter mating with the individual fluesofthe other series, means for circulating diiferent temperatureIiontrolling mediums through said series of tions.

4. In combination with a furnace having a heating'chamber provided withtwo series of longitudinal flues, means for circulating ues respectivelyin opposite direc" iums respectively through the a heatin medium throughone series of flues in one irection and means for circulating anindependent cooling medium inthe op posite direction through the otherseries of flues, the discharge of the heating and cooling mediums beingindependent of each other. I v,

5. In combination with a furnace having a heating chamber provided withlongitudinal flues surrounding the same, means for introducing a-cooling medium into one endof said flues and dlscharging the same attheopposite end of said flues into the interior' of the heating chamber.

6. In combination with a fujrnace'provided with a heating chamber havinglon- I gitudina'l flues surrounding the chamber, means for introducing acooling medium into said flues at the receiving end of the chamber anddischarging the same into the delivery end of the heating chamber.

7 In combination with a furnace having a heating chamber provided withlongitudinal flues surroundin the same, means for introducin cold airinto the flues at the receiving en of the heating chamber, and a nozzlecommunicating with the op osite ends of the flues and arranged'to eliverthe heated air into'the interior of the heating chamber at'its deliveryend.

8. In combination with a furnace provided with a heating chamber toreceive the raw ore at one end and discharge the residue at the'oppositeend and having twoseries of longitudinal flues surrounding the chamberside by side and terminating at 'theinopposite ends respectively in twodifferent circular planes, means for the intro- I 1888.4t8i5 duction ofcold air into one series of fines at the receiving end of the furnace,means whereby the air discharged from the opposite ends of said linesmay be introduced into the heating chamber, and means for in troducingheating ases into the ends of the other series of fines at thedischarging end of the furnace.

9. In combination with a furnace provided with a heating chamber toreceive the raw ore at one end. and discharge the resi due at the otherend, and having two series of longitudinal surrounding fiues, means forthe introduction of cold air into one series of fines at the receivingend of the furnace, means whereby the air discharged from the oppositeends of said fiues may be introduced into the heating chamber, and meansfor introducing heating gases into the ends of the other series of fiuesatthe discharging end of the furnace. I

10. In combination with a furnace having a heating chamber provided withsurrounding longitudinal fines, means for the int-roduction of air intosaid fiues at the receiving end of the furnace, means whereby the airissuing from the opposite end of the said fines may be discharged intothe heating chamber, and means for deflecting the air in its passage tothe heating chamber and dis charging the same to the outside.

11. In combination with a furnace having a cylindrical rotating heatingchamber 'provided with surrounding fines, means for the introduction ofcold air into the ends of the lines at the receiving end of the furnace,a nozzle connected with the opposite ends of said fines and arranged todirect the air into the heating chamber, and a valve for con trollingthe flow of the 'air through the nozzle.

12. It furnace having a cylindrical. rotary heating chamber providedwith two series of lines having their ends at one end of the furnacetermimitingrespectively in difi'erent circular concentric lines.

13. A. furnace having a cylindrical rotary heating chamber provided withlongitudinal surrounding fiues disposed in a circular field at a pointbetween the ends of the furnace".

and terminating at the ends of the furnace respectively in differentcircular concentric lines. v

M. A furnace having a cylindrical rotary heating chamber provided withtwo series of longitudinal fiues surrounding the cham her, with thefiues of one series alternating with those of the other, the fines ofone series terminating at theend of the furnace in 'one circular lineand the fines of the other series terminating at the same end of thefurnace in a difierent circular line concentric with the first.

15. A furnace provided with a rotary cylindrical heating chamber havinglongitudinal fines surrounding the chamber side by side and terminatingat opposite ends in medium into the same fiues to retard combustion.

18. In combination with a furnace provided with a heating chamber havingsur rounding longitudinally extending fines, means for circulatingeither air or heating gases in one direction through certain of saidlines, and means for circulating cold air in the opposite directionthrough the other fines.

19. In combination with a furnace provided with a heating chamber havingsurrounding heating fiues, an auxiliary furnace and connections betweenthe auxiliary furnace and heating lines to deliver the prodnets ofcombustion to said fiues.

20. In combination with a furnace pro vided with a rotary cylindricalheating chamber having two series of surrounding longitudinal finesarranged side by side with the opposite ends of the fiues of one seriesterminating respectively in lines concentric with but different from thelines in which the opposite ends of the other series of finesrespectively terminate, the said furnace having two fixed chambers atone end with which the two series of lines respectively communicate atthat end, and having at the opposite end. two fixed chambers with whichthe two series of fines respectively communicate at that end.

i :21. A furnace provided with a cylindrical rota y heating chamberhaving two series of surrounding longitudinal lines, the said furnacebeing further provided at each end with two chambers communicatingrespectively with said series of fines.

22. In combination with furnace having a rotary cylindrical heatingchamber formed with two series of longitudinal fines extending side byside and surrounding said chamher, an air blower connected w1th,theends;

of the fiues of one series at the receiving end of the furnace, means atthe opposite ends of said fines for directing the air from the blowerinto the interior of theheating chamher at its delivery end, and anauxiliary furnace connected with the ends of the other series of fluesat the delivery end of the furnaces, the o posite ends of said. lastnamed series of ues being arranged to discharge the products ofcombustion passing through them from the auxiliary furnace.

23. In a furnace the combination with a fixed casing at the receivingend formed with an annular chamber having its rear wall disposed in aplane transverse to the axis of the chamber, of a horizontal rotarycylinder constituting a heating chamber and formed with longitudinalsurrounding flues adapted to communicate with the annular Y chamber, theend of said cylinder being formed to abut flatly and closely-against the15 wall of the annular. chamber; whereby the leakage of air-into theheating chamber will be prevented. i y

In testimony whereof we hereunto set our hands this twentyrfifth day ofNovember, 20 1908, in the presence of two attesting witnesses.

JAMES B. LADD. DAVID BAKER.

Witnesses:

Lomsn B. Momus, S. HORACE MYERS.

